Jessica Ho is a joint Ph.D. Candidate in Demography and Sociology at the University of Pennsylvania. Her research interests include demography, medical sociology, health disparities, aging and the life course, health care systems, stratification, population health, international comparisons, and quantitative methods. Her research focuses on the social determinants of health, aging, and mortality, with particular emphasis on explaining differences in health across populations. She has been engaged in two main areas of research: she examines variation in population health among developed and developing countries and health inequalities within the United States. One strand of her research uses international comparisons to address the question, “Why is life expectancy in the United States so much lower than in other high-income countries?” Her second strand of research examines social, behavioral, and institutional factors that contribute to racial/ethnic and socioeconomic health disparities.